I turn my work (if it's more than 3 stitches)
cast on the left needle
and then turn back around and resume knitting

What do you mean? If you turn your work you are just casting on the right needle then because it was your right now your left. I am a little confused and trying to understrand what you are saying. The working yarn is on your right needle so if you turn your work the left needle was your right so what is the difference by turning it.